Copy system

ABSTRACT

A rapid copy-making system for producing copies for example on photographically slow material such as a diazo, vesicular &#39;&#39;&#39;&#39;Kalvar&#39;&#39;&#39;&#39; or contact speed silver halide by producing an intermediate image from photoelectrophoretic material and more or less immediately using this intermediate image to contact print the slow photographic material. A separate light source of high intensity exposes the recently created photoelectrophoretic intermediate image for imaging the photographically slow material.

Unite States Patent Rhodes et al. Feb, 1, 1972 [54] COPY SYSTEM [72]inventors: Warren L. Rhodes, Rochester, N.Y.; Vergffiyjgr g ii 2 :32: IL.M tOklh C't,Okl. arqual: a a oma ly a Attorney-James J. Ralabate,David C. Petre and Barry Jay [73] Assignee: Xerox Corporation, Stamford,Conn. Kesselman 22 Pl d: A 28 1970 1 57 ABSTRACT [2}] Appl. No.: 67,812

A rapid copy-making system for producing copies for example a onphotographically slow material such as a diazo, vesicular [52] U.S. Cl.355/3, 96/l.n, 355/12 Kalvar" or Contact Speed Silver haiide byproducing an inter- [51] 'f Cl 15,00,602 15/14 mediate image fromphotoelectrophoretic material and more [58] Field 0 Search 4, l l, 12,17, or less immediately using hi intermediate image to Contact 96/1print the slow photographic material. A separate light source of highintensity exposes the recently created photoelec- [56] References cuedtrophoretic intermediate image for imaging the photographi- UNITEDSTATES PATENTS Cally Slow 3,427,242 2/ 1969 Mihajlov ..96/1 .3 X 5Claims, 2 Drawing Figures /3\ VACUUM SOURCE PATENTEU rm H97? 3,639,049

VACUUM INVTORS WARREN L. RHODES VERNON L. MARQUART A TTOR/VEV COPYSYSTEM This system relates to imaging systems and more particularly tosystems employing photoelectrophoretic image intermediates.

The invention herein evolves around the new photoelectrophoretic imagingsystems disclosed in US. Pat. Nos. 3,383,993; 3,384,448; 3,384,565 and3,384,566. They disclose how to produce a visual image at one or both oftwo electrodes between which photoelectrophoretic particles suspensionsare placed. The particles are photosensitive and appear to undergo a netchange in charge polarity or a polarity alternation by interaction withone of the electrodes upon exposure to activating electromagneticradiation. Mixtures of tow or more differently colored particles cansecure various colors of images. The particles will migrate fromone ofthe electrodes under the influence of an electric field when struck withenergy of a wavelength within the spectral response curve of the coloredparticles. The colors may be used independently or in subtractive colorsynthesis using particles of yellow, magenta and cyan colored particles.In a monochromatic system, i.e., a system employing particles ofsubstantially one color, the particles will migrate if energy of anywavelength within the panchromatic spectrum of the particle responsestrikes the particle.

Certain terms of art have been used in conjunction with thephotoelectrophoretic imaging system. A definition of these terms ishelpful. The injecting electrode" is so named because it is designed tooptimize charge exchange with activated photosensitive particles duringimaging. The term photosensitive" when used in reference to particlesrefers to particles which, once attracted to the injecting electrode,will alter their polarity and migrate away from the electrode under theinfluence of an applied electric field when exposed to activatingelectromagnetic radiation within their spectral response curve. The termsuspension" may be defined as a system having solid particles dispersedin a solid, liquid or gas.

Nevertheless, the suspension preferred for use in the disclosurc hereinis of the general type having a solid suspended in a liquid carrier. Theterm imaging electrode" is used to described that electrode whichinteracts with the injecting electrode through the suspension and whichonce contacted by activated photosensitive particles will minimizecharge exchange with the particles. The imaging electrode is coveredwith a dielectric surface composed of a material having a volumeresistivity preferably in the order of or greater ohm-cm. and aconductive core member.

For photoelectrophoretic imaging to occur it is though that these steps,not necessarily listed in the sequence that they occur, take place: (I)migration of the particles toward the injecting electrode due to theinfluence of an electric field; (2)

the generation of charge carriers within the particles when struck withactivating radiation within their spectral response curve; (3) particledeposition on or near the injecting electrode surface; (4) phenomenaassociated with the forming of an electrical junction between theparticles and the injecting electrode; (5) particle charge exchange; (6)electrophoretic -migration toward the imaging electrode; and (7)particle deposition on the imaging electrode. This leaves an image onthe injecting electrode that is optically positive inlight and in color.

Mechanisms associated with the photoelectrophoretic imaging systemnormally have a transparent electrode, preferably being the injectingelectrode, through which the photosensitive pigment particles areexposed to electromagnetic radiation. These particles absorb theradiation, undergoing the phenomena of charge exchange, and migrateunder the influence of the applied field between the injecting andimaging electrodes.

It is an object of this invention to reduce the steps required forproducing copies of objects on slow photographic materials. Anotherobject of the invention is to increase the speed for making copies onphotographic materials. Yet another object of this invention is toimprove imaging with selected photographic intermediates. A furtherobject of this invention is to reduce the cost and time for formingmicrosize images.

These and other objects of this invention will become apparent to thoseskilled in the art after reading the description in conjunction with theaccompanying drawings wherein:

FIG. 1 schematically represents an embodiment of this invention in anautomatic machine for producing copies of an original through anintermediate, and

FIG. 2 is an alternative schematic representation of this invention.

The invention herein is described and illustrated in specificembodiments having specific components listed for carrying out thefunctions of the apparatus. Nevertheless, the invention need not bethough of being confined to such a specific showing andshould beconstrued broadly within the scope of the claims. Any and all equivalentstructures known to those skilled in the art can be substituted forspecific apparatus disclosed as long as the substituted apparatusachieves a similar function. It may be that other processes or apparatuswill he invented having similar needs to those fulfilled by theapparatus described and claimed herein and it is the intention herein todescribe an invention for use in apparatus other than the embodiment orapplication shown.

FIG. 1 illustrates apparatus for using a photoelectrophoretic imagingsuspension in an image configuration as the intermediate or original forcontact or close-spaced copying with a duplicating film. The duplicatingfilm may be typically a diazo or vesicular Kalvar or a contact speedsilver halide material. One benefit of the system is that if specialhigh intensity illumination is required for the reproduction materialsuch as a high intensity UV source, that need not effect the imageformation on the intermediate master used for the contact or closecopying, or need it effect originals that may otherwise be harmed by thehigh intensity illumination. In the illustration of FIG 1 the lightsource It) illuminates an original 11 shown in the form of a moving filmstrip which is projected through a lens 12 and off a mirror 13 to theimaging position between an injecting electrode 14 and an imagingelectrode 15. The injecting electrode is composed of a transparent glassmember coated with a transparent electrically conductive material suchas, for example, tin oxide. The imaging electrode has a surface composedof a dielectric material sleeve and an electrically conductive substratewhich is connected to a potential source. The injecting electrode iselectrically connected to ground to provide a field between theinjecting and imaging electrodes. An imaging suspension dispenser 16meters the imaging suspension 17 to flow past the imaging positionbetween the two electrodes. Imaging suspension removed by the imagingelectrode 15 is evacuated through the vacuum system schematicallyrepresented by the numeral 18. The suspension remaining on the injectingelectrode 14 is in an image configuration and may be partially fixed sothat it will not readily be removed by contact with the copy material.The fixing takes place by unit such as the drying unit 19. The dryphotoelectrophoretic imaging suspension will cling fairly well to itssupport cylinder, the injecting electrode 14 without rubbing off ontotheduplicating film 20. A high intensity light source 21 with a slottedreflector 22 illuminates the copying imaging position between theinjecting electrode 14 and the copy film support drum 23 holding theduplicating film 20 on its surface. The surface of the electrodes 14 and15 are moved in rolling contact or near contact at substantially thesame speeds to avoid smearing the'image as it is formed. Actually, bothelectrodes may be rotated by external means such as a motor and gearingsystem. Alternatively, one may drive the other by friction.

The copy drum 23 rotates with a surface velocity substantially equal tothe surface velocity of the injecting electrode '14. lt carries with itthe copy film20 supplied from a supply spool- 24 and wound around atakeup reel 25. ldler rollers 26 and 27 maintain the film 20 tightagainst the surface of the support 23. The copy film 20 is sensitive tolight in the spectrum emitted by'the high intensity illumination source21. By

beaming the illumination through the image formed of the imagingsuspension 17 maintained in contact or close proximity to the copy film20, the copy film is modified by the light passing through the imageformed of the suspension 17. After the required number of copies aremade from the image formed on the injecting electrode 14, the injectingelectrode 14 is cleaned by a vacuum system 28 which scrapes and cleansthe loosely adhered dried image-pattern suspension 17 from the surfaceof the injecting electrode 14. To permit multiple copies to be made froma single-imaged intermediate, a program device 30 modifies the imagingcycle of the photoelectrophoretic imaging system by stopping the flow ofsuspension from the dispenser 16 such as, for example, by closing thevalve 31, removing the imaging electrode from contact at the imagingposition with the injecting electrode 14 and also turning off theillumination source 10. The cleaning mechanism 28 is also disengaged sothat the image formed on the injecting electrode-support cylinder 14 maypass any selected number of times by the copying station to be imagedonto the duplicating film 20. When the desired number of copies are madeon the copy film 20, the programmer 30 engages the cleaning mechanism 28and reinstitutes the imaging cycle for the photoelectrophoretic imagingsystem.

FIG. 2 shows a modified apparatus for achieving the invention describedherein. In this schematic apparatus a monochrome photoelectrophoreticcomposition such as, for example, phthalocyanine dispersed in a wax isapplied by feed rolls 37 to a rotating injecting electrode cylinder 36which is transparent and has a transparent electrically conductivecoating on its outer surface. The photoelectrophoretic suspension ismoved to a uniformly thin film by smoothing roll 39. The material can besoftened with a spray of solvent from the solvent=spray mechanism 40.The rotating injecting electrode then passes into contact with animaging electrode transfer cylinder where a light image strikes thesuspension at the interface thereof. The light image may be a reducedimage from a selected original maintained at the object plane of a lens42 which projects light rays from the original to a mirror 44 and to animage plane coinciding with the interface of the two electrodes 36 and41 at the imaging position on the transfer cylinder 41. The electricalpotential supplied to the backing of backing 46 of the transfer cylinder41 will determine whether the image transferred to the transfer cylinderis optically positive or negative.

In the reproduction section of the transfer cylinder located away fromthe interface of the transfer cylinder with the injecting electrodecylinder 36 a copy or duplicating film material 48 passes the exposurestation 50. A sheet or web of the duplicating film is kept in rollingcontact with the transfer cylinder 41. It is exposed at the exposurestation 50 by a high intensity illumination source 52. A backing plate54 maintains the duplicating film 48 in close contact at the exposurestation 50.

A suitable film, or paper, supply 56 is maintained and fed by a rollersystem through the exposure station and then to a heating source 58containing, for example, radiant heaters 59 for development for thosetypes of film requiring infrared or heat development after exposure tosuch high intensity sources as ultraviolet ray emitters. The developedfilm or paper would then be fed into a copy-catch tray 60 for removal byan operator when convenient.

Although many current used would prefer a reduced-size 7 copy device forbringing originals to a microsize for easy storage and reproduction thatis not a necessary limitation of this apparatus and in fact any sizereproduction including magnifications of greater than I to l ormagnifications equal to or less than I to l are possible withoutdiverting from the scope of the invention.

In order to prepare the injecting electrode 36 for further imaging, thecounter image 62 is removed from the surface of the cylinder 36 bycleanup rolls 63 using a solvent 64 to remove the imaging suspensionformed as a counter image from the surface of the injecting electrodecylinder.

Various drives and mechanical and electrical connections are not shownin the schematic representation of the attached figures. However, it isunderstood that means known to those in the art can be used to implementthe drawings shown to cause them to function in the manner describedherein. Such means and all equivalents thereof including methods ofcolor balancing and photographic filtering as well as machine design arenot fully described herein since they are known to those skilled in theart and could readily be applied by such persons to the inventionclaimed in light of the disclosure herein.

While this invention has been described with reference to the structuresdisclosed herein and while certain theories have been expressed, it isnot confined to the details set forth; and

this application is intended to cover such modifications or changes asmay come within the purposes of the improvements and scope of thefollowing claims.

What is claimed is:

1. Apparatus for photoelectrophoretic imaging comprising in combinationa first electrode,

a second electrode adapted for movement in close proximity to said firstelectrode,

means to apply an imaging suspension between said first and secondelectrodes,

means to move said first and second electrodes at substantially the samesurface speed,

means to project an image onto said suspension between said electrodes,

means to apply an electric field across said suspension at saidelectrodes whereby an image is produced on said second transparentelectrode, means to illuminate the image at a copy position whereat thesecond electrode is adapted to maintain the image produced between saidfirst and second electrodes,

support means interfacing with the second electrode at the copy positionon the image-bearing surface of the second electrode,

means to pass a photosensitive copy medium on the support means insynchronous movement with the second electrode surface for activation bysaid means to illuminate for exposing the photosensitive copy medium tothe image on the second electrode.

2. The apparatus of claim 1 wherein said means to illuminate radiates inthe ultraviolet region of the spectrum.

3, The apparatus of claim 1 wherein the copy medium supportable on saidsupport member is support to contact the image on said second electrode.

4. The apparatus of claim 1 including cleaning means to removesuspension from the second electrode after interfacing with said supportmeans.

5. The apparatus of claim 4 including programming means to disengagesaid means to apply imaging suspension, said means to project an image,said means to apply an electric field and said cleaning means frominteracting with said second electrode.

1. Apparatus for photoelectrophoretic imaging comprising in combinationa first electrode, a second electrode adapted for movement in closeproximity to said first electrode, means to apply an imaging suspensionbetween said first and second electrodes, means to move said first andsecond electrodes at substantially the same surface speed, means toproject an image onto said suspension between said electrodes, means toapply an electric field across said suspension at said electrodeswhereby an image is produced on said second transparent electrode, meansto illuminate the image at a copy position whereat the second electrodeis adapted to maintain the image produced between said first and secondelectrodes, support means interfacing with the second electrode at thecopy position on the image-bearing surface of the second electrode,means to pass a photosensitive copy medium on the support means insynchronous movement with the second electrode surface for activation bysaid means to illuminate for exposing the photosensitive copy medium tothe image on the second electrode.
 2. The apparatus of claim 1 whereinsaid means to iLluminate radiates in the ultraviolet region of thespectrum.
 3. The apparatus of claim 1 wherein the copy mediumsupportable on said support member is support to contact the image onsaid second electrode.
 4. The apparatus of claim 1 including cleaningmeans to remove suspension from the second electrode after interfacingwith said support means.
 5. The apparatus of claim 4 includingprogramming means to disengage said means to apply imaging suspension,said means to project an image, said means to apply an electric fieldand said cleaning means from interacting with said second electrode.